Glossary: Dice Making Terms

New to dice making? This glossary covers the vocabulary you’ll encounter across our guides — from resin chemistry to mold design to the geometry of a d20.

A

Alcohol Ink A dye-based colorant that creates organic, flowing patterns in resin. The basis for petri dice and galaxy effects.

B

Blank An unfinished die after demolding — still has sprues, flash, or rough faces that need sanding and polishing.

Bubble Trapped air in cured resin. The most common defect in dice casting. Eliminated with pressure pots at 40+ PSI.

C

Cap Mold A two-piece mold where each die face is formed by a flat cap, producing sharp-edge dice with crisp geometry. Harder to use than sprue molds.

Catalyst (Hardener) Part B of a two-part resin system. Triggers the exothermic chemical reaction that cures liquid resin into a solid.

Cure Time The duration required for resin to fully harden. Typically 24-72 hours depending on resin type and temperature.

D

d20 (d4, d6, d8, d10, d12) Standard polyhedral dice used in tabletop RPGs. The number indicates the count of faces. A full polyhedral set includes seven dice.

Demolding Removing a cured die from its mold. Requires care to avoid chipping edges or tearing the silicone.

E

Epoxy Resin A two-part thermosetting polymer (resin + hardener) used for dice casting. Preferred over polyester for clarity and low odor. See best resin for dice.

Exothermic Reaction The heat generated during resin curing. Excess heat causes yellowing, cracking, or premature cure. Managed by controlling pour volume and ambient temperature.

F

Flash Thin excess resin that seeps between mold halves. Removed during sanding.

FOMO (Fear of Missing Out) Dice Dice with dramatic, one-of-a-kind color patterns created by intentional resin manipulation. Each set is unique.

G

Galaxy Dice A technique using layered mica powder, glitter, and alcohol ink to create deep-space nebula effects inside resin. See galaxy dice guide.

Glow Powder (Strontium Aluminate) Phosphorescent pigment that charges under light and glows in darkness. Used in glow-in-the-dark dice.

I

Inclusion Any object embedded inside a resin die — flowers, gold leaf, gears, glitter, or miniatures. See resin dice inclusions.

Inking The process of filling engraved numbers on a die with paint or ink for readability. See dice inking guide.

L

Liquid Core A hollow die containing a sealed chamber of colored liquid (usually glycerin) that moves when rolled. An advanced technique. See liquid core dice.

M

Master Die A precision-machined or 3D-printed die used to create silicone molds. The quality of the master determines the quality of every cast.

Mica Powder Finely ground mineral pigment that creates pearlescent, metallic, or color-shifting effects in resin. See best mica powder.

Mix Ratio The proportion of resin to hardener (typically 1:1 by volume for epoxy). Incorrect ratios cause soft, sticky, or uncured dice. See resin mixing ratio.

P

Petri Dice Dice made by dropping alcohol ink into uncured resin, creating organic tendril patterns that resemble petri dish cultures. See petri dice guide.

Polyhedral Having many faces. In dice making, refers to the standard RPG dice shapes: d4 (tetrahedron), d6 (cube), d8 (octahedron), d10 (pentagonal trapezohedron), d12 (dodecahedron), d20 (icosahedron).

Pot Life (Working Time) The window after mixing resin and hardener during which the mixture remains pourable. Typically 20-45 minutes for dice resins.

Pressure Pot A sealed steel tank that applies 40-60 PSI air pressure during curing, compressing bubbles to invisible size. Essential for clear dice. See pressure pot guide.

PSI (Pounds per Square Inch) Unit of pressure. Dice casters typically cure at 40-60 PSI.

R

Resin The base polymer (Part A) that, when combined with hardener, cures into a solid plastic. See best resin for dice.

S

Salt Water Float Test A balance test where dice are floated in saturated salt water and spun repeatedly. Consistently landing on the same face indicates imbalance. See dice balance test.

Sharp Edge A die with crisp, unrounded edges — the hallmark of handmade artisan dice. Requires cap molds and careful hand-finishing. See sharp edge dice.

Silicone Mold A flexible rubber mold used to cast resin dice. Available as sprue molds (single opening) or cap molds (two-piece). See dice mold guide.

Sprue The channel through which resin enters a closed mold. Also refers to the cured resin plug left in that channel, which is cut and sanded off after demolding.

Sprue Mold A one-piece mold with a single pour opening (sprue). Easier to use than cap molds but produces rounded edges that require tumbling or sanding.

U

UV Resin A single-part resin that cures under ultraviolet light in minutes. Used for small repairs and fills, not full dice casting.

W

Wet Sanding Sanding resin with water as a lubricant to prevent heat buildup and clogging. Standard technique for finishing dice through progressive grits. See wet sanding guide.

Y

Yellowing Discoloration of cured resin over time, caused by UV exposure or excess exothermic heat during curing. Prevented with UV-resistant resins and proper cure conditions. See yellowing prevention.